We plan to insolubilize each of the fractions of chicken erythrocyte and chicken liver histones on an insoluble support (Agarose) and to then measure the binding of non-histone chromosomal (NHC) proteins isolated from the same tissues to the histone-agarose. Our objective is to attempt fractionation of some of the NHC proteins by affinity chromatography on the assumption that histones can form specific and tight complexes with NHC proteins. Proteins isolated by this method will be characterized (molecular weight, amino acid composition, possible phosphorylation sites) and tested for their ability to form complexes with the different classes of histones and with histones from a different tissue. Tissue specific differences in NHC protein content will also be checked.